BMI1 and glioblastoma: This ultimately results in increased expression of SOX2, a transcription factor responsible for bequeathing stem cells with the capacity for unrestricted self-renewal and proliferation (36) and upregulated in progenitor CSCs in GBM (2) and Bmi1, a protein implicated in brain development and contributes to the aberrant self-renewal and proliferative nature of glioma stem cells (36).